<form class="system-pool-add">
  <div class="input-append">
    <input name="pool" required maxlength="255"
           type="text" placeholder="Pool name"
           pattern="[^\s/]([^/]*[^\s/])?"
           title="System pool name of up to 255 characters, excluding /"/>
    <button class="btn" type="submit" data-loading-text="<i class='fa fa-spinner fa-spin'></i> Adding&hellip;"><i class="fa fa-plus"></i> Add</button>
  </div>
</form>
